1. Field of the Invention
The present invention relates to a bearing means for masses that compensate secondary forces due to inertia and secondary moments of inertia, whereby the compensating masses are supported in a housing that is flanged to a crank case and are driven via a toothed wheel, that is connected to a crank web arranged adjacent to a symmetry plane of a crank shaft and intermeshes with a first gear wheel. The first gear wheel is fixedly connected to the first one of the compensating masses and intermeshes with a second gear wheel that drives a second one of the compensating masses.
2. Description of Related Art
It is known from U.S. Pat. No. 3 667 317 to compensate secondary forces due to inertia by providing two compensating shafts that are arranged parallel to the crank shaft and are driven via a toothed wheel by the crank shaft such that they rotate in opposite directions relative to one another at the double rotation speed of the crank shaft. A toothed wheel of the crank shaft is arranged at a crank web that is adjacent to a symmetry plane of the crank shaft and intermeshes with a first gear wheel of the first compensating shaft, whereby the second compensating shaft is driven by a second gear wheel that intermeshes with the first gear wheel. Compensating masses are fixedly connected to the two compensating shafts. The compensating shafts are supported with both ends at a housing that is flanged to a crank case. Compensating shafts, gear wheels, and compensating masses are separate pieces and must be assembled in a difficult mounting step. Due to the required assembly, the exact positioning and permanent coordination of the compensating masses and the gear wheels which is important for the desired complete mass compensation is difficult to achieve. Since the compensating masses are arranged on both sides of the crank shaft, they may not be arranged between two adjacent cylinders, because the compensating masses may not exceed a certain length in order to avoid a collision of the compensating masses with the crank web respectively the piston rod. On the other hand, the diameter of the toothed wheel that is connected to the crank web may not be too large in order to avoid contact of the toothed wheel with a piston in its lower dead center position. This means that the compensating shaft may not be positioned too far away from the crank shaft center so that the radial extension of the compensating mass is thereby limited.
It is therefore an object of the present invention to provide a bearing means for compensating masses of the aforementioned kind which are constructively designed such that, when considering the smallest possible piston rod gauge, the rotation axes of the compensation masses may be positioned as close as possible relative to the crank shaft center whereby the compensating masses still may be placed between two adjacent cylinders